{
\def\sym#1{\ifmmode^{#1}\else\(^{#1}\)\fi}
\begin{tabular}{l*{2}{c}}
\hline\hline
            &\multicolumn{1}{c}{(1)}&\multicolumn{1}{c}{(2)}\\
            &\multicolumn{1}{c}{ingred}&\multicolumn{1}{c}{ingred}\\
\hline
ai          &       0.633***&       0.676***\\
            &     (0.202)   &     (0.205)   \\
\hline
R2          &       0.027   &       0.045   \\
Observations&         312   &         312   \\
Round controls&          No   &         Yes   \\
\hline\hline
\multicolumn{3}{l}{\footnotesize Standard errors in parentheses}\\
\multicolumn{3}{l}{\footnotesize * p<0.10, ** p<0.05, *** p<0.010}\\
\end{tabular}
}
